


Not All Omegas Are The Same

by FiveFootFrankie



Category: Mulan (1998), Supernatural
Genre: A/B/O, AU, Alpha!Dean, Alpha/Beta/Omega Dynamics, Angels, Crossover, Demons, Gordon is a dick, M/M, Threats of Rape/Non-Con, mulan - Freeform, nothing happens though, omega!cas, someone get's stabbed, threats of non-con outside of Castiel/Dean, very mild violance
Language: English
Status: Completed
Published: 2014-07-24
Updated: 2014-07-24
Packaged: 2018-02-10 07:10:57
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,623
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2015799
Author URL: https://archiveofourown.org/users/FiveFootFrankie/pseuds/FiveFootFrankie
Summary: <blockquote class="userstuff">
              <p>The demons are planning an attack against Michael and the Army of Angels are drafting one alpha or beta from every family. Castiel decides to hide his sent and run away to join instead of his mother to keep his brother from growing up without his parents. What would happen if the Army ever found out he's an omega, or when Castiel realizes he has grown feelings for his commanding officer?</p>
            </blockquote>





	Not All Omegas Are The Same

**Author's Note:**

> I suck at descriptions. Personally I think I suck at writing too, but whatever.   
> I had the idea of a Mulan AU but Cas being an omega instead of a girl and I wanted to read one, but I doubted there was one. If you read or write one you should totally give me the link, I would love to read it
> 
> I edited it, but I'm not exceptionally good at editing, so all mistakes are mine

 

Castiel groaned as his mother attempted to fix his hair again. “Mom. It won’t go down.”

Naomi sighed. “Well maybe if you ever brushed it instead of just leaving it all messy.” Castiel shrugged and his mother gave up. She straightened his tie and smiled at him. “You’ll be great, honey. And some day you’ll make an alpha very happy.” Naomi stepped back and the rare moment between them was gone. “Let’s go,” she said and walked outside. It could make you sick to mate after your early thirties and omegas were so rare; especially omegas with angel blood-no matter how small-so there were people who would match make alphas and betas that preferred omegas.

Castiel followed his mother outside so they could head to the match makers house. Time passes slowly as a large, constantly smiling man asked him questions and made notes about his answers. The man would have reminded Castiel of Santa if he’d been older. When he was finished with his questions, he reviewed the information while Castiel just sat there, bored.

“You’re too… dominant for an omega,” he said finally.

“What?”

“That right there.” Castiel raised his eyebrows. He hadn’t pegged the guy as the type to be discriminant against omegas. “Not that there’s a problem with you speaking without being asked,” he corrected quickly, “it’s just that many don’t. And when they do, they do it with extremely politeness. You’re very blunt. Like a beta.”

“Is that a bad thing? I mean, couldn’t I just find someone who’s interested in betas?”

“You could but it might be hard. You act much like a beta in some ways but completely like an omega in others. It might be difficult to find an alpha or a beta who likes the mixture. I would love help, but people come to me for a specific type of omega. I wouldn’t be able to do much,” he said apologetically. Castiel sighed dejectedly and went home.

His mother smiled excitedly when Castiel entered but her face fell when Castiel didn’t share her excitement.

“What did he say?” she asked as she put her younger son, Samandriel, on the ground.

“He said I’m too dominant. Too much like a beta.” Her mother made a face as if by saying that Castiel had personally offended her. She was about to say something when knocking at the door interrupted them. They hurried to open the door to see a full blooded angel standing outside.

The man handed her an envelope. “The demons are planning an attack against Michael. The angels are drafting at least one alpha or beta from every available family.”

Castiel’s eyes widened. “But you can’t! She has a son to take care of.” The angel stared at Castiel, surprised by his outburst.

“You should teach your omega better respect,” he sneered and walked away.

Naomi turned to Castiel with a disapproving look on her face. “He’s right, Castiel. You can’t just interrupt people like that, especially not an alpha angel.” Castiel frowned but said nothing. “I’ll leave you and Samandriel in Hester’s care. With Inias gone she could probably use the help.” Castiel opened his mouth to protest, but his mother cut him off. “Go to bed, Castiel. It’s been a long day and I’ll be leaving in the morning.” She kept her face impassive, but Castiel could see in her eyes how much she didn’t want to leave. Castiel nodded anyway and went up to his room, but didn’t go to sleep. He couldn’t just let his mother leave. Odds were that she would die fighting the demons and Castiel wouldn’t let his brother grow up without a mother or a father. He packed a bag and waited until everyone was asleep.

When his mother had finally gone to bed he snuck out to the back garden, looking for a specific plant. It was an herb called Nightshade that could be put in little cloth bag and it masked the sent enough that you couldn’t tell if someone was an alpha, beta or omega, but didn’t mask the sent enough to be suspicious. Every omega knew how helpful it could be during a strong heat. Castiel hadn’t met anyone his body found was a suitable mate so he didn’t have a heat yet; he would be set for a few months.

Castiel took the envelope from his mother’s room and left in its place the small charm his father had given him. It was Greek and depicted that he was an omega and proud of it. He kissed his brother goodbye before disappearing into the night.

 

 

 

Castiel stood in the forest near the entrance to the camp. “What am I gonna do?” He started pacing. “I can’t do this—No. I can. I will. Just act like a beta. Act like an angel. Act like the angel your ancestors were. You can do this.” Castiel took a deep breath, made sure his scent was undetectable, and walked toward the entrance.

“And who are you?” The alpha in charge of signing everyone in looked over Castiel judgmentally.

“James. James Novak.”

“I didn’t know Novak had another kid.”

“Three, but Castiel is an omega and Samandriel is too young,” Castiel replied nervously.

“Whatever,” the man said, handing Castiel his papers and calling for the next in line.

As Castiel walked in and looked for his tent he noticed two people standing, watching a dark haired man ride away on his horse, leading a troop of Army recruits. The younger man with dirty blonde hair and bright green eyes whispered something that sounded like “good luck, father,” to himself. The other man made a face at him and walked away.

The blonde man gave Castiel a look when he realized he’d been staring. Castiel quickly walked away, muttering, “We really need to work on your people skills.”

                                                                                                                                                   

By the next morning all the trainees had arrived and were called to the center of the camp by the blond man from the day before. He introduced himself as Captain Dean Winchester who would be training the troops, and the other man from the day before as Gordon Walker of the Angels Council, who would be giving General John Winchester the report on how they did when they met up with him near the Devil’s Gate.

Winchester looked over the troops, contemplatively. He grabbed a bow and arrow and shot it at the top of a large poll. “Speight,” he said and a short beta with wavy hair stepped forward. “Get the arrow.”

The short man smirked. “Easy.”

Winchester stopped before he started climbing, hanging a weight around each of his wrists. “These represent discipline and strength. You will need both to reach the arrow and to defeat the demons.” Speight looked a little less confidant now, but tried climbing. He didn’t make it very far. No one could get more than a quarter of the way up the poll. Winchester sighed and dismissed everyone for the day.

 

Training went slowly and it was hell for Castiel. Besides the fact that omegas were naturally weaker than alphas or betas, Castiel had never been a very physical person. Sure, he helped his mother when she needed it, but not much beside that. Target practice, hand to hand combat, or firing canons. No matter what it was, Castiel couldn’t seem to get it right. The only thing keeping him afloat was his angel blood.

Captain Winchester looked at Castiel sadly and sighed before walking into his own tent. A new sense of determination burning in his gut and Castiel walked outside and picked up the weights, tying them to his hands. Castiel stared up the poll, mentally reviewing the information of what everyone had tried on the first day of training. Castiel smiled when he figured out how he would get the arrow and started climbing. When Captain Winchester exited his tent the next morning, Castiel threw the arrow to his feet and smiled from where he sat atop the poll. From that day on, Castiel tried even harder in training and eventually was able to beat even the captain in hand to hand combat.

He smiled softly at Castiel from his place on the ground. “I think you’re ready.”  Dean stood and made his way to Gordon’s tent to tell him the troops had completed their training and were ready to meet with the general for the next move. Castiel was walking back to the barracks when he overheard Gordon telling Captain Winchester that he was a bad captain and the troops would never be ready to face the demons. Captain Winchester slammed the door and stormed away.

“For the record, I think you’re a great captain,” Castiel said, not expecting him to respond. Winchester only took a moment to glance back at him before walking away.

Castiel sighed, wanting to hit himself. He couldn’t like his captain. It just couldn’t happen. Winchester would never like him back and even if he did, Dean liked the nice beta Jimmy. He definitely wouldn’t like the dominant little omega that Castiel was. Dean seemed to prefer the winged angels in the camp anyway. What was the point of being an angel without any angel powers? Castiel growled to himself. All his angel blood had gotten him was the certainty that he would never mate.

Despite Gordon’s opinion, Captain Winchester made the announcement and they left the next morning to meet up with the general in Wyoming.

 

“You got anyone waiting for you at home?” A beta with a British accent-Balthazar, Castiel thought his name was-asked the beta from the first day of training.

Gabriel smirked. “No, I’m more of a free spirit. I prefer unattached alphas. You?”

“An omega. Rachel. What about you, Jimmy?” he asked, elbowing Castiel. 

Castiel glanced at them. “No.”

“No strong, dominant alpha?”

“Or a beta to take turns with?”

“Even a submitting omega?”

He averted his eyes nervously. “Um… no.”

Gabriel smirked and leaned into Castiel’s space. He opened his mouth to speak when Captain Winchester stopped at the top of a hill. Winchester had a solemn look on his face and they all stepped up to see what he was looking at. Castiel gasped when he saw what was around him; the iron railroad tracks were broken and ripped up.

“Search the town for survivors,” Winchester ordered, pointing to the nearby town that had been destroyed. Gordon was standing next to him, looking over what was left of the town. “I don’t understand,” he muttered, “my father should have been here.”

“Captain,” Gordon interrupted Dean’s thoughts and pointed to the edge of the small valley where the General and his troops had camped. The tents had all been burned to the ground, not even the few personal artifacts the Army had brought had survived. When they returned with no survivors, Captain Winchester mounted his horse and faced the recruits once again.

“The demons are moving quickly, so we need to stop them before they can open the Devil’s Gate. We’re the only hope for Michael now. Move out.” As they reach the other end of the valley they hear a howl and an arrow hits Captain Winchester in the shoulder.

“Get out of range,” Winchester orders. The alphas and betas fall back and take cover before firing canons at the oncoming demons. They’re down to the last canon when the arrows stop coming and look to see the leader of the demon army, Azazel, standing at the top of the valley, more demons appearing behind him. Dean pulls out his sword etched with spell work to kill a demon. “Prepare to fight. You won’t be able to completely kill the demon, but you might be able to incapacitate them.” Castiel notices a few of the demons sliding on loose rocks as they descend and takes the last canon from Balthazar’s grasp. He runs forward, resting it on a rock and pulling out the flint to light it. As Azazel and the demons grow closer, he shoots the canon, aiming for a large rock at the top of the valley.

“He was right in front of you! How did you miss that?” Winchester yelled. Azazel got close enough to slash at Castiel’s retreating form, ripping open his bag containing the herb to mask his smell, before a rock fell on him.

“Run!” Castiel yells to the troops. As he runs by, he grabs Captain Winchester and pulls him into a small cave and out of the way of the falling rocks. When the rocks settled, the rest of the troops came and quickly moved the rocks that had blocked the entrance so Castiel and Captain Winchester could get out.

“We got them!” Gabriel yelled. “Give them some space.” Captain Winchester stood first and turned to Castiel.

“You are absolutely insane, but you saved me. For that I owe you.” He smiled and held out a hand to help Castiel up. The omega gasped and fell to his knees clutching his side. “Jimmy, what’s wrong?” Castiel pulled his arm away from his side to see it covered it blood. “I need a medic!” Winchester yelled and that was the last thing Castiel heard before the world went black.

 

When Castiel came to he was laying on a mat inside a tent. He looked around confused for a moment before Captain Winchester entered the tent.

“Dean,” he gasped, sitting up, and that was when he noticed the scent. The tent was full of the scent of an omega.

Dean’s pupil’s dilated slightly when he scented the air. “So it’s true?”

“I can explain,” Castiel tried to say, but he was already leaving the tent again.

Gordon came in, pulling Castiel up and dragged him outside. He pushed Castiel to his knees, holding his face back by his hair. “I knew there was something wrong with you,” he growled. “He’s an omega.”

Everyone gasped, staring at Castiel in shock or hate, some wrinkling their nose in disgust, but the one that hurt the most was the sad look on Dean’s face.

“Disrespectful little omega,” someone sneered and the crowd slowly trickled away.

“My name is Castiel. I did this to save my mother.”

“This is an act of high treason,” Gordon said as if Castiel didn’t already know.

“I didn’t mean for it to go this far.” Castiel cried out in pain when Gordon pulled Castiel’s face up farther, bearing his neck.

“Do you know what the punishment is for high treason?” Gordon asked, getting close to Castiel’s face. By now the only other person standing there was Dean. Gordon leaned closer and scented the omega’s neck, causing him to whimper quietly. “You smell delicious,” he growled in Castiel’s ear.

“Walker, that’s enough,” Dean said.

Gordon gave Dean a hateful glare. “Why?” he snapped. “He’s a dirty little omega and the penalty is death. No one would even know.”

“No,” Dean stated simply, his voice dripping with hatred. He pulled out his sword and ordered for Gordon to step back. Castiel lowered his head in anticipation and was surprised when the only thing that happened was Dean’s sword being thrown to ground in front of him. Castiel and Gordon both looked to Dean in surprise. “A life for a life. My debt is repaid.” With that Dean turned and walked away, ordering for everyone to move out.

“But-“ Gordon protested.

“I said, move out,” Dean barked, pulling Gordon close by his shirt “and if you’re not on your horse and following us, I will have you charged with hate crimes against an omega.” Gordon sent Castiel a venomous look and the troops departed.

Castiel sat on his knees in the remains of the burnt town and watched the Army recruits depart. He let out a scream that turned into a cry as he curled in on himself. “I never should have left home. I never should have let it go this far.” The omega can feel can feel that something in his body accepted Dean as an appropriate mate for protecting him and Castiel prays that he doesn’t go into heat. He stands to fetch his horse and ride home when he hears rocks start to move. Fearing another rock slide, the omega hides, but watches as Azazel claws his way out of the rocks.

Two alpha girls and three alpha males pushed their way out of the rocks and move to where Azazel is waiting. Azazel is seething at the fact that the Devil’s Gate was destroyed by rocks and yells in anger, back handing one of the men after he says something. Azazel makes an order that Castiel is too far to hear and they leave.

“They’re still going after Michael,” Castiel gasps to himself. He gets on his horse and rides the other way around the town toward the Hall of Angels. Castiel rides to the city, just far enough away so the demons won’t hear or smell him. He arrives in time to hear them announcing Captain Dean Winchester and his troops as the saviors of Michael.

Castiel rides up next to the captain. “Dean, the demons are alive,” he says, urgently.

“You shouldn’t be here Castiel.”

“Please you have to believe me.”

“Go home,” Dean replies, turning away.

“I saw them come out of the rocks.” He turns to Gabriel and Balthazar. “Be on the lookout. I know they’re here.” Castiel hops off his horse and runs into a crowd of people listening to Michael give a speech about their saviors. “Sir, Michael is in danger,” he says to the first alpha he came to. The man turns away in disgust. Castiel growls and moves on to a beta who gives him a similar response. Castiel groaned in frustration, watching Michael talking to Dean from the top of the long staircase they were standing on.

Out of nowhere a large, black hell hound shot up the steps. From the shadows Azazel and the three male demons approached Michael. Dean unsheathed his sword, but before he could even make a move towards any of them, the two female demons ran from the crowd and attacked Michael, pulling him inside the Hall of Angels and locking the doors behind them. Dean, Gabriel and Balthazar were trying to bust open the door with a statue. Castiel looked around desperately for some way to get in.

“Guys! I have an idea,” Castiel yelled. He ran over to a little decorative garden where Nightshade was growing. Gabriel and Balthazar ran over to where Castiel was pulling leaves off the plant. “Put this on you somewhere and make your clothes look… slutty,” Castiel ordered. He pulled off his over shirt and ripped it into pieces. “And put this somewhere on you, too. That way you’ll smell like an omega.”

Dean came over too. “Is there anything I can do?”

Castiel looked over Dean. “You’re too dominant to pass for an omega… I know! Come on,” he said, motioning for them to follow him around the side of the palace. They snuck in through the kitchen. “Dean, lead us through and if anyone sees us pretend you’re bringing us to the angel’s quarters for them.”

“Are you sure that’ll work, Cas?” Dean asked.

“Yes. No one would even question an alpha giving a couple omegas to someone, no matter the laws.” Dean looked at Castiel with sympathy but continued walking.

“Who’s there?” one of the two demons asked as they approached.

“Omegas. Concubines for the angels. Do you know where they are? We can’t find their chambers.”

“Wait. Aren’t you-“ the male demon started, but Castiel kicked him in the crotch.

“No,” he replied and punched the girl in the nose. Gabriel lays a hand on each of the demons heads and their eyes glow blue before they open their mouths as if to scream and black smoke comes out. Castiel stared at him. “You’re part angel.”

“Not enough for wings, but enough to send a demon back to hell. What about you?” he asked as the other three demons entered the room.

Dean slashed two of them with their swords and Gabriel exorcised the other one, looking exhausted after.

“Not enough to do anything.” Gabriel leaned against the wall. “Gabe, you stay here and guard. Balthazar and Dean, let’s go,” Castiel said and hurried up the stairs behind Dean to the balcony. Azazel raised his sword, preparing to strike Michael when Dean blocked the blow with his own blade and push Azazel to the ground. “Balth, Michael,” Castiel ordered. Balthazar pulled out the ripped over shirt and grabbed Michael by the waist.

“Sorry, your, uh, angel-ness, but hold on,” he said and threw the shirt over a string of lanterns, using it to slide to the ground.

“No,” Azazel growled, yellow eyes glinting in the light. He stood, kneeing Dean in the stomach and head butting him before shoving him to the ground.

Castiel looked between Dean, Azazel’s forgotten sword and Michael safe on the ground before grabbing the sword and cutting the rope to the lanterns.

“NO!” Azazel yelled, reaching for the rope as Castiel ran to Dean’s side.

“It’ll be okay, Dean,” he whispered, pulling out the dagger Dean kept hidden. Castiel put the enchanted dagger away as Dean pushed him away from the blow Azazel was about to deliver. Azazel back handed Dean before pulling him close by his shirt.

“You ruined it. You ruined everything.”

“No,” Castiel said. “I did.”

Azazel turned his harsh gaze on the omega. “You’re the one who blew up the Devil’s Gate.” His eyes widened when he scented the air. “And you’re an omega? Why you little-” He rushed at Castiel, but the omega had been expecting it and was already climbing out onto the roof. Being bulkier and more out of shape than Castiel, it took Azazel a minute to climb onto the roof, but by that time Castiel was running towards the other end of the roof.

Castiel stopped at the end of the roof and turned around; eyes wide and looking scared out of his wits like a good little omega should.

“End of the line,” Azazel said, with a satisfied smile. “I didn’t get Michael, but I’ll take you in compensation. A submissive little omega, and an angel at that, but just barely.” Azazel pulled his blade again, but Castiel hit him on the weak spot of his elbow and twisted his wrist so the sword fell from his hand and to the edge of the roof.

“I will never submit,” Castiel growled, pulling the dagger, “to you.” With the final words he stabbed Azazel in the heart and twisted. Castiel turned them around and went to push Azazel off the roof but Azazel grabbed his arm at the last second.

“If I go down, you’re coming with me,” he wheezed.

Castiel squeezed his eyes closed as he fell, but his descent was stopped by two hands as he passed the balcony and was dragged back onto it. “Dean!” Castiel gasped when he saw who’d pulled him back up. “Gabriel. Thank you.” They exited the palace and walked down the stairs, meeting Balthazar and Michael half way down.

Gordon walker came storming up the stairs the next second. “You’re lucky we didn’t kill you the first time,” he growled, pointing a finger at Castiel. Dean, Gabriel and Balthazar moved to stand between the, causing Gordon to stop in his tracks. “Step aside, this filthis not worth protecting.”

“Cas is a hero,” Dean growled.

“He’s an _omega.”_

Dean stepped forward, pulling Gordon forward by his shirt. “Listen here, dick bag-“

“Enough,” Michael said, cutting Dean off.

“Sir,” Dean starts, but Michael silences him, motioning for them to let Castiel through. Dean steps to the side, followed by Gabriel and Balthazar. Castiel steps up, bowing his head respectfully.

“I have heard quite a bit about you, Castiel. How you ran away from home and hid your scent, impersonated a soldier, deceived your commanding officers, and,” Michael paused and Castiel winced, waiting for the worst to come. “You’ve saved us all.” Michael bowed his head. Gordon looked appalled, but quickly followed the action. Castiel looked around noticing not only had his friends also bowed, but everyone surrounding the palace had their heads lowered in recognition of their savior. Michael raised his head, white wings shuffling behind him, and turned to Gordon. “Walker, make sure this omega is put on the Council of Angels.”

Gordon looked disgusted. “There are no positions open,” he replied smugly.

“Very well, he can have your job.” Gordon’s mouth fell open, but he quickly snapped it shut and went silent.

Castiel bowed his head again. “With all due respect, Michael, I have been away from home far too long.”

Michael nodded. He opened his hands and a few full blood angels approached them and took a small piece of their grace, the blue substance flowing from them into Michael’s open palms. He moved his head to Castiel’s head, pushing the Grace into him with the words, “Take this, the grace of an angel, so you and your family will always remember what you have done for me.” He closed his eyes in concentration and waved a hand over Castiel and suddenly he had two large black wings. “And take these, so the world will know what you have done for the angels.” Castiel gasped as the wings on his back fluttered with anxiety.

Castiel stares at his hands, suddenly seeming so different with Grace running though his body, before wrapping his arms around the angel in front of him. He stepped back and bowed again. “Thank you.” Castiel goes down the line, bidding his friends farewell and even received an awkward nod from Gordon. He finally reached Dean and stared into the pretty green eyes he’d been entranced with since his first day of training.

“You, um. You fight good,” Dean muttered.

Castiel smiled timidly. “Thank you.”

Dean laughed to himself. “God, how did I not realize you were an omega? You’re so kind and shy.” A blush rose on Castiel’s cheeks and his smile grew before he turned away. He mounted his horse and waved one last time before departing home.

 

 

Upon arriving home, Castiel cautiously opened the door and entered the house, unsure if his mother would still be angry after so long away. His mother walked into the room and froze, staring at him in shock. Castiel bowed his head, acting more like the omega he is than he has in over a year.

“Mother, I’ve been granted my own wings and grace,” he said. “Th-they’re gifts to honor our family.” Naomi brushed off his words, wrapping Castiel and his new wings in the tightest hug she’d ever given him.

“I’m so glad you’re okay,” she whispered. The next thing they knew, Samandriel came into the room announcing sadly that someone was here for Castiel.

“Cassie!” he yelled, realizing his brother was home. Castiel grinned and picked up his younger brother, walking to the door where Dean was waiting awkwardly.

“Oh,” Dean said upon seeing Castiel holding the young child. “I didn’t realize you had kids. I’ll just, uh, go.” He tried to mutter a goodbye and leave but Castiel cut him off.

“Dean, he’s my brother,” Castiel said and put Samandriel down. A blush grew on Dean’s cheeks as he tried to stutter out a response.

“You should stay for dinner since you brought Cassie home,” Samandriel stated.

Dean turned to the younger boy. “Actually,” he said with a chuckle. “He brought me home.”

“Well, you should stay for dinner anyway, ‘cause Cassie likes you.”

Castiel’s cheeks instantly flushed. “Alfie!”

Dean smiled at Castiel. “I would love to stay for dinner.”


End file.
